1. Field
The following description relates to an optical recording medium, an apparatus and method of manufacturing an optical recording medium, and an apparatus and method of recording/reproducing data of an optical recording medium allocated with wobble address suitable for a capacity of a high density recording disc.
2. Description of the Related Art
Optical discs (such as compact discs (CD), digital versatile discs (DVD), Blu-ray discs (BD), and high density digital versatile discs (HD-DVD)) have been developed to have high density recoding capacities. Such a high density recording capacity may be obtained using two methods. First, a recording density per surface area may be increased using a short wave laser. Second, a recording layer of a disc may be raised. Optical discs and recording/reproducing systems having higher densities are being developed using a laser having the same wavelength as a BD, which currently has the highest density.
FIG. 1 is a diagram illustrating an optical disc 10, which is an optical recording medium having data tracks. Referring to FIG. 1, spiral groove tracks and spiral land tracks are formed on the optical disc 10. The tracks may be wobbled with a predetermined frequency in order to show address information.
FIG. 2 is an example of the tracks of an optical disc 10, shown in FIG. 1. Referring to FIG. 2, a wobble signal is recorded while manufacturing an optical disc 10. In other words, the wobble signal is recorded while recording a groove track 20 using a laser beam during a mastering process by changing forms of both walls of the groove track 20. The forms of both walls of the groove track 20 are changed by adding a certain amount of offsets to the laser beam in a radius direction of the optical disc 10. The groove tracks 20 are formed in a spiral form in a predetermined interval from the center of the optical disc 10, and a land track 30 is formed between the groove tracks 20.
FIG. 3 is a diagram illustrating a conventional wobble address. Referring to FIG. 3, an optical disc 10 includes a recording unit block (RUB) 400, which is a unit for recording data. A wobble address corresponding to the RUB 400 includes three address units (ADIPs) (i.e., ADIP #1 100, ADIP #2 200, and ADIP #3 300).
FIG. 4 is a diagram illustrating a detailed structure of the wobble address of FIG. 3. Referring to FIG. 4, each ADIP includes a sync part and a data part. For example, ADIP #1 100 is 83 bits. Specifically, a sync part 110 of 8 bits identifies a front part of the ADIP #1 100, and a data part 120 of 75 bits stores actual data of address information.
The data part 120 includes 15 ADIP blocks 121 through 123, and each ADIP block 121 through 123 includes a monotone bit and 4 ADIP bits. In other words, the data part 120 includes 15 monotone bits and 60 ADIP bits. A detailed structure of 60 ADIP bits 500 is illustrated in FIG. 5.
FIG. 5 is a diagram illustrating a more detailed structure of the wobble address of FIG. 4. Referring to FIG. 5, 60 ADIP bits 500 include address data 510 in 24 bits, auxiliary data 520 for recording additional information (such as a recording condition) in 12 bits, and parity data 530 for correcting an error in the address data in 24 bits.
When the optical disc 10 is multi-layered, the address data 510 includes layer information 511 indicating a layer number in 3 bits, RUB information 512 indicating an address of an RUB in 19 bits, and an address in RUB 513 showing an address of an ADIP in an RUB in 2 bits.
FIG. 6 illustrates a bit configuration of the address data 510 of FIG. 5. Referring to FIG. 6, one nibble is 4 bits, and each instance of the address data includes address data in 6 nibbles, auxiliary data in 3 nibbles, and parity data in 6 nibbles.
In the structure of the wobble address as described above, the wobble address is expressed in 24 bits. In particular, excluding the top 3 bits indicating a layer number and the bottom 2 bits indicating a location in one RUB, the number of bits showing one RUB is 19 bits. In other words, 219 different RUBs may be shown, where each RUB has a capacity of 2048*32 bytes (64 Kbytes). Accordingly, a capacity of a recording medium that may be shown in 19 bits is as follows.64 Kbytes*219=34,359,738,368 bytes=approximately 34 Gbytes
However, optical discs having recording densities of over 34 gigabytes have been developed. Thus, using a conventional ADIP address structure, the capacity of a recording medium cannot be entirely expressed.
Accordingly, a method of coping with a high density optical disc while minimizing changes to a conventional system is required.